This tool generally makes possible more convenient handling of the removal and installation of a roll pin that retains a trigger guard in a lower receiver on a conventional M16/M4 family weapon when the installation or removal of the trigger guard, hence the installation or removal of the retaining roll pin, is desired. As will be appreciated by those in the gun repair trade, the disassembly or reassembly of the trigger guard and allied elements (e.g., the roll pin) of such weapons is a challenging, tricky and painstaking activity sometimes resulting in damage to the lower receiver, thus greatly needing improved assist. The disclosed tool handily is a great addition and assists in such activities.
The description as follows includes directional designations such as up, down, left, right, lateral, transverse, longitudinal, top, bottom, vertical, and the like, that are taken from the perspective of a firearm (e.g., a conventional AR-10/AR-15/M16 family, style, platform, or pattern rifle and M4 pattern carbine, and variants thereof) as typically held and operated by a user.
The description assumes the level of knowledge held by an ordinary armorer, gunsmith, repair or assembly technician, user, operator, maintenance personnel, and the like for a conventional AR-15/M16 pattern rifle and M4 pattern carbine, and variants thereof, and the respective components and operation thereof. The environment forms no part of the invention. Likewise, designations such as “a”, “an”, and “the” are not to be construed to be limited to a singular item or action unless apparent from the context or definitely described as such.
As used herein, elements having numbers more than 9 and less than 100 generally refer to conventional elements known in the art by one having ordinary skill with respect to a rifle, firearm, weapon, carbine, and the like; generally AR-10, AR-15/M16 rifle, M4 carbine families; while elements number 100 and above refer to the present invention, or elements, components, and the like thereof. Like numbered elements generally refer to the same element; however, the like numbered elements may include a suffix “L” to designate the left side element and a suffix “R” to designate the right side element when left and right elements are mirrors of each other.
Conventional elements include:    10: lower receiver assembly;    12: trigger guard;    14: trigger guard retention roll pin;    16: pistol grip (hand grip) mounting flange;    20 (20L, 20R): trigger guard retention flange (tang, ear, wing, and the like), roll pin flange;    22 (22L, 22R): trigger guard roll pin hole (lateral hole in the flange 20);    30: hand grip retention screw hole;    32: hand grip retention screw;    34: selector (safety, fire control lever);    40: pin punch;    42: hammer;    44: pad, block, or the like;    TO: tang offset (inward offset of the trigger guard tangs 20 from the outer surfaces of the lower receiver 10);    U: User, armorer, gunsmith, repair or assembly technician, operator, maintenance personnel, aid the like.
As further understood by those having ordinary skill in the art, the conventional M16/M4/AR-15 family weapons are made to an exacting technical data description that is agreed upon by manufacturers of not only the firearms but the numerous aftermarket accessories as well; and, as such, provides interchangeability and modularity within and between manufacturers using such designation. As such, designation of the subject firearms as being within M16/M4/AR-15 family weapons provides the indication (designation) of de facto standardization of the components so designated. Thus, such designation is distinct and particular as used in connection with claims directed thereto.
During assembly and repair operations of AR-15/M16 pattern (style or family) rifles and M4 pattern (style or family) carbines (i.e., weapons), and variants thereof (referred to as guns, weapons, or firearms hereafter), the trigger guards (i.e., mechanism, assembly, devices, etc.) of such weapons, as is well known to those skilled in the art of the assembly, maintenance, and repair of the weapons, are often removed and installed (or reinstalled). Such operations may include tasks such as but not limited to initial firearm assembly, installation of new trigger guards to replace damaged trigger guards, upgrading of trigger guards, etc.
Referring to FIGS. 1-3, FIGS. 1-3 illustrate conventional, prior art AR-15/M16 rifle and M4 carbine pattern lower receivers 10. FIG. 1 is a left side elevation of a bare (stripped) lower receiver 10. The lower receiver 10 shown on FIG. 1 is intact. FIG. 2 is an isometric view from the upper, right, front with inset 2A which is an isometric view from the upper, right, rear that illustrates the user, U, using the conventional tools (i.e., the punch 40, the hammer 42, and the pad 44) during the process of trigger guard retention roll pin 14 installation or removal. FIG. 3 is an isometric view of the receiver 10 from the lower, left, rear that illustrates an example of a flange 20L that was broken during an unfortunate but all too common failed attempt to install the trigger guard retention roll pin 14.
During assembly, repair, and replacement operations of the AR-15/M16 pattern rifles and M4 pattern carbines (i.e., firearms, weapons, etc.) 10, and variants thereof, a trigger guard element 12 of the lower receiver 10 may be installed or removed. As understood by one of skill in the art, e.g., an armorer, gunsmith, user, operator, repair or assembly technician, maintenance personnel, and the like, U, the rear portion of the trigger guard 12 is held (retained) in the lower receiver 10 by a tension pin (e.g., roll pin, split pin, C pin, spiral pin, coil pin, etc.) 14 that is inserted between (driven into) lateral holes 22 (e.g., holes 22L and 22R) within laterally opposing first and second flanges (tangs, tabs, ears, etc.) 20 (e.g., ears 20L and 20R) on the lower receiver subassembly 10 of the firearm forward of the hand grip mounting region (e.g., a hand grip flange 16) and through an intervening lateral hole (channel, passage, etc.) in the rear of trigger guard 12. The most commonly used tension pin is a roll pin (split pin). As such, hereinafter, the tension pin 14 is non-exclusively referred to as a roll pin. The hand grip flange 16 includes a threaded hole 30, which matingly receives a threaded screw or bolt 32 (see, for example, FIGS. 5-7) to retain a hand (pistol) grip (not shown) as part of the assembly process, as understood by one skilled in the art.
As illustrated on FIG. 2 including inset 2A, conventional tools and a conventional process that have been used for AR-15/M16 rifle and M4 carbine 10 trigger guard roll pin 14 installation and removal include a pin punch (i.e., punch with a flat tip) 40, a hammer 42, and an impact resistant pad or block 44 that is placed behind the lower receiver 10 at the roll pin flange 20 that is opposite the side from which the roll pin 14 is inserted. The pad 44 is typically placed on a work bench or table (not shown). The user, U, manually positions the trigger guard 12, laterally aligns the roll pin 14, and drives the roll pin 14 into position through the holes 22 via taps, hits, blows, and the like to the punch 40 with the hammer 42. Alternatively (not illustrated), the roll pin 14 may also be pressed (squeezed) into position through the holes 22 (e.g., pressed using a C-clamp, pliers, or the like) laterally positioned across the roll pin tangs 20; however, the pressing of the roll pin 14 approach also has the same occasional, undesirable consequences (i.e., breakage of a roll pin flange 20, described below in connection with FIG. 3) as drying the pin 14.
Unfortunately, as illustrated on FIG. 3, even when care is taken by attempting to remove burrs, lubricate, and correctly align the roll pin 14 with both of the lower receiver flange holes 22L and 22R (and the intervening hole through the rear of the trigger guard 12) and the impact pad 44 is carefully positioned, occasionally the roll pin 14 insertion or removal process will go awry and one of the roll pin flanges 20 is broken off the lower receiver 10. As the lower receiver 10 is a costly and federally regulated (i.e., registered as a firearm) part, breaking the lower receiver 10 is a potentially costly burdensome occurrence. On FIG. 3, the distance, TO, illustrates a tang offset by which the trigger guards 20 are offset inward from the outer lateral surfaces of the receiver 10.
The broken receiver 10 may be rendered inoperable by the user and discarded. Alternatively, users who break one or both roll pin flanges 20 may: (i) repair the broken flange 20 with expensive welding, grinding, and refinish processes; (ii) repair the broken flange 20 with a relatively weak epoxy joint and hope that the broken flange 20 does not encounter any mechanical stress; or (iii) hide the broken flange 20 with a commercially available pistol grip that incorporates a trigger guard (e.g., STARK SE-1 grip, MAGFUL MIAD (registered trademark) grip) which may be costly and uncomfortable to the user. So common is the breakage of the flange 20, that the replacement grips that hide the broken roll pin flange 20 are often referred to, sometimes with Schadenfreude, as “the grip of shame”. Clearly, a better approach is to not break the roll pin flange 20.
A conventional approach to avoid breaking the roll pin flange 20 is to not use a roll pin 14, instead to: tap threads or install thread adapter inserts into the holes 22, and install low profile head screws to retain the trigger guard 12. However, such an approach has the deficiencies of being expensive, requires special tools and skills to perform, may defeat the swing down (“winter”, i.e., thick glove use) feature of the trigger guard 12, the trigger guard 12 may be loose (flop, wiggle), and the screws may back out unless additional steps such as adding retention compound are taken which may make removal of the screws difficult.
Thus, there is a need and a desire for a system and a process that overcomes one or more of the deficiencies of conventional devices and processes.